The plan right now is to put a 2001 Ranger 4.0 SOHC into my 1997. I've been looking through the EVTM and service manuals for both vehicles pondering the electrical issues. I know that most everything under the hood will need to change for the new engine and I am also going to take the opportunity to customize the harness in the rest of the truck. I would like to use the older modules for this...as in pre-2000 or so GEM, remote/alarm module, etc. On the 2001 there is a data network that all of the various modules are connected to which is not present in the earlier years. There is also a different set of modules for the years. My question is this: If everything elsewhere in the truck is wired correctly, should it matter to the PCM that it is basically the only 2001 computer/module on the truck? I have looked over the PCM connector pinout and I don't see any connections to the rest of the truck that will be a problem for what I am doing. In fact, even though the service manual implies the PCM shares the same bus as the other modules, the connector on the PCM shows no such connection. It looks to me to be fairly independent. Any thoughts?
1997 XLT Extended Cab 4.0 SOHC 2WD Manual